solid-core-reactivity-model

SolidJS components run only once because the framework uses fine-grained reactivity and direct DOM bindings instead of virtual DOM diffing. Reactive updates target specific DOM nodes through signals and effects, entirely avoiding the component re-execution model found in React.

Debug SolidJS tracking issues by analyzing how signals, memos, and effects form a reactive graph. Inspect ownership trees and tracking scopes to ensure dependencies are correctly captured within the intended execution context without leaking.

SolidJS ownership governs the lifecycle of reactive scopes, automatically cleaning up child effects and memos when a parent scope disposes. Use onCleanup to manually register disposal logic tied to the current ownership tree.

Memos in SolidJS cache and track derived reactive values within the ownership tree. They prevent redundant recomputation by ensuring downstream effects only re-execute when the memo's value actually changes, optimizing the reactive graph.

SolidJS reactivity updates the DOM directly through fine-grained tracking, bypassing virtual DOM diffing entirely. Unlike React's component-level re-rendering, SolidJS executes component functions once and relies purely on signals and effects for state propagation.